QUADRATIC AND ENERGY ESTIMATES OF THE PARTIAL-RESPONSE OF RIBBED PANELS

Two formalisms of the response of a ribbed uniform panel excited by a line drive are considered. In the first a quadratic analysis (QA) of t he linear response is obtained. In this response phases among the resp onses of the bays are preserved and accounted for. (A bay is the porti on of the panel that lies between two adjacent ribs.) The preservation of the phases yield responses that exhibit the phenomena of pass and stop bands and of localization and delocalization when the separations between adjacent ribs are equal. In the second an energy analysis (EA ) of the response is obtained. The response is estimated in terms of t he energy densities in the individual bays. In this formalism the phas es among the responses of the bays are inconsequential. Therefore the phenomena of pass and stop bands and of localization and delocalizatio n are not manifested in the EA response. It is thus suggested that for malisms that are akin to the statistical energy analysis (SEA) and SEA itself cannot be expected to exhibit some of the features in the resp onse of a complex structure, especially if the structure is composed o f a number of regular substructures; e.g., the identical bays in a rib bed panel. The generic example presented in this paper illustrates tha t in certain situations and for certain purposes the missing features in the EA response, as compared with the QA response, may be significa nt.